1. Field of the Invention
The present invention relates to a process to prepare maltose powder, specifically, to a process to prepare a stable maltose powder containing crystalline beta-maltose hydrate.
2. Description of the Prior Art
As disclosed, for example, in Japanese Patent Publication No. 3,937/79 and Japanese Patent Laid-Open No. 92,299/85, maltose powders containing crystalline beta-maltose hydrate have been manufactured by concentrating a high-purity maltose liquid to about 70-80 w/w % (moisture content of 20-30 w/w %), adding a seed crystal to the syrup, spray-drying a massecuite wherein crystallization of beta-maltose hydrate has proceeded to 30-50%, and ageing the resultant powder to a moisture content of 6 w/w %.
Conventional process, however, has the drawbacks that it consumes a relatively large amount of energy for drying at ambient temperature a maltose syrup having a relatively high moisture content (i.e. 20-30 w/w %) wherein crystallization of beta-maltose hydrate has been initiated by the addition of a seed crystal and this increases the manufacturing cost of maltose powder, as well as that a vigorous heating during the drying undesirably melts the resultant crystalline beta-maltose hydrate to hinder the attainment of a consistently high-quality maltose powder.